Magnetic circuits that include ferromagnetic (FM) wires have allowed the fabrication of spintronic devices, that is, devices that are adapted to make use of an interaction between a current of spin-polarized electrons and a magnetic field to fulfill their prescribed functions, such as for example, the function of serving as non-volatile memory devices or as reconfiguration logic devices. The internal computational state in magnetic devices is encoded by the magnetization direction, such that, even where power is removed from the magnetic circuit in question, the magnetization direction may remain, potentially for tens of years. Spintronic devices have been known to be formed including metal layers of an integrated circuit as their electrodes.
In order to provide a three-dimensional configuration of logic devices, the prior art still uses CMOS structures built up on a semiconductor device layer supported by a wafer, and bonds different such wafers together to achieve the three-dimensional structure. However, wafer-bonding is an expensive process, and offers only a limited number of bonded connections.